Prenatal exposure to methyl mercury or methylazoxy methanol: effects on early postnatal motor activity.
de Groot-DM; Kuijpers-M; O'Callaghan-J; van Dael-M; Gundersen-H; Hartgring-S; van der Horst-L; Kaufmann-W; Otto-M; Pakkenberg-B; Pelgrim-M; Waalkens-I; Lammers-J
Toxicologist 2005 Mar; 84(Suppl 1):216
Developmental Neurotoxicity testing according to specific test guidelines is required for disclosure of the potential adverse effects of industrial chemicals and agricultural pesticides on the developing nervous system. Motor activity is included in these guidelines as an apical behavioural endpoint with the intent to evaluate a range of potential effects on the developing nervous system. It is known that different activity measures may be differently affected by chemicals and drugs, depending on the dose and type of agent. Also, other nervous system functions may be changed and may lead to changes in motor activity. In addition, motor activity may be indirectly affected as a result of systemic toxicity (e.g. adverse effects on body temperature or body weight). In research, supported by the American Chemistry Council (ACC Ref.nr. 1847), we studied motor activity in rats, prenatally exposed to methyl mercury chloride (MeHg) or methylazoxy methanol acetate (MAM) (5 dose levels each). MAM and MeHg were chosen as model neurotoxicants. They both affect brain morphology during development. MeHg, however, primarily causes systemic toxicity. Motor activity was tested on PN 13, 17, 21 and 60-62, as indicated in the EPA guideline OPPTS 870.6300 for Developmental Neurotoxicity testing. The results showed that prenatal exposure to MAM or MeHg affected early postnatal motor activity differently. The results will be shown and the relevance of the effects with regard to developmental neurotoxicity will be discussed in relation to the results obtained for other endpoints (maternal and developmental in-life data, and pathology).
Prenatal-exposure; Mercury-compounds; Neurotoxicity; Agricultural-chemicals; Pesticides; Nervous-system; Toxic-effects; Neurotoxins; Neurotoxic-effects; Laboratory-animals; Animals; Animal-studies; Exposure-levels; Exposure-assessment; Teratogenesis; Teratogens; Teratology
The Toxicologist. Society of Toxicology 44th Annual Meeting and ToxExpo, March 6-10, 2005, New Orleans, Louisiana